Title :
Droop improvement in high current range on PSS-LEDs
Author :
Tanaka, Shoji ; Zhao, Yiwen ; Koslow, I. ; Pan, C.-C. ; Chen, Hua-Tsung ; Sonoda, J. ; DenBaars, Steven P. ; Nakamura, Shigenari
Author_Institution :
Mater. Dept., Univ. of California, Santa Barbara, CA, USA
Abstract :
The droop property of blue GaN light emitting diodes (LEDs) has been improved by creating a 9 quantum well (QW) LED on a patterned sapphire substrate (PSS). The droop ratio was improved from 45.9 to 7.6%. At a wavelength of 447%nm, and with standard on-header packaging, the 9QW PSS-LED had an output power of 27.6%mW and an EQE of 49.7% at a current of 20%mA. The output power of the 9QW PSS-LED remains linear with increasing drive current, even up to relatively high current density, and the EQE is almost constant.
Keywords :
III-V semiconductors; gallium compounds; light emitting diodes; semiconductor quantum wells; wide band gap semiconductors; 9QW PSS-LED; EQE; GaN; blue light emitting diode; current 20 mA; droop ratio; external quantum efficiency; on-header packaging; patterned sapphire substrate; power 27.6 mW; quantum well LED;
Journal_Title :
Electronics Letters
DOI :
10.1049/el.2010.3306
